Tedder with adjustable rake rotors

ABSTRACT

A hay tedder adapted to be supported from a tractor and which includes a plurality of raking rotors supported for rotation about generally vertical, inclined axes. The tedder includes a main frame for connection with the tractor and a carrier beam pivotally supported from the main frame with the rake rotors being supported from the carrier beam and also supported from travelling wheels. An angle adjustment mechanism is provided to change the inclination of the rake rotors to obtain optimum spreading of the hay or grass crop. The structural association of components enables adjustment of the angle of the rake rotors to be automatically accompanied by a corresponding height adjustment of the travelling wheels which support the rake rotors thereby avoiding the necessity of independently adjusting the rake rotors and travelling wheels.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention concerns a tedder of the type having a main frame forconnection with a tractor and a carrier beam pivotally supported fromthe main frame for pivoting about a horizontal axis. A plurality of rakerotors are rotatably supported from the carrier beam with each rotoralso being supported by a travelling wheel having a height adjustmentwith respect to the carrier beam which has an angle adjustmentmechanism. In such a tedder the angle adjustment mechanism for pivotingthe carrier beam makes it possible to change the inclination of the rakerotors with respect to the travelling direction to obtain optimumspreading of the mown grass crop. Height adjustment means for thetravelling wheels make it possible to change the inclination of the rakerotors such that the desired height of the rake springs above the groundis maintained constantly in the direction of forward travel.

2. Description of the Prior Art

In the known tedders of the present type the angle adjustment and theheight adjustment are effected independently of each other, e.g. bymeans of hydraulic cylinders as shown and described in DE-B2-26 13 027,or by means of screw spindles and cord drives as shown and describede.g. in DE-C2-25 45 712.

SUMMARY OF THE INVENTION

The object of the invention is to provide a tedder of the present typewhich is so adapted that adjustment of the angle of the rake rotors isautomatically accompanied by a corresponding height adjustment of thetravelling wheels.

This object is achieved by an angle lever pivotally mounted on thecarrier beam such that the axis of rotation of the angular lever isdisplaced when the carrier beam is pivoted to change the angle, and isrotated because of the connection of one arm with a point fixed withrespect to the main frame such that the height adjustment means isdisplaced to change the wheel height. This adjustment can be performedfrom the cab of the tractor in the operation of the tedder.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be explained more fully below with reference to thedrawing, in which

FIG. 1 is a vertical, partially sectional view of an embodiment of thetedder of the invention with a divided drive shaft,

FIG. 2 is a corresponding vertical view of a second embodiment having athrough-going drive shaft, and

FIG. 3 is a vertical section through an amended embodiment of a part ofthe tedder.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In FIG. 1, 10 is a part of a main frame which is adapted to be suspendedfrom the three-point suspension of a tractor in a generally known, notshown manner. A hollow carrier beam 11, which has a substantiallyrectangular cross-section and extends perpendicularly to the travellingdirection in the entire length of the tedder, is pivotally suspendedfrom the main frame 10 by means of arms 12, which are rotatable about ashaft 13 extending between nose members 14 on the main frame. Anupwardly extending, angular bracket 15 is secured on the upper side ofthe carrier beam 11, and a nut 16 is rotatably arranged at the outer endof the bracket. A screw spindle 17, which can be rotated from the cab ofthe tractor in a manner not shown, extends smoothly through a sleeve 18which is rotatably mounted in an upstanding bracket 19 secured to themain frame 10. A lock disc 20 is secured on both sides of the sleeve 18on the screw spindle 17, preventing axial displacement of the screwspindle which extends threadedly through the nut 16. The advantage ofthe mechanism described above is that the carrier beam 11 can pivotabout the shaft 13 by rotation of the screw spindle 17.

A plurality of rake rotors, only one of which is shown in the drawing,are rotatably suspended from the carrier beam. The rake rotor, which isgenerally designated by 21, has a hub disc 22 mounting, e.g. by means ofscrews or rivets 23, a plurality of arms 24 which carry rake means 25.The hub disc 22 is secured on a hollow shaft 26 which is rotatablymounted by means of ball bearings 27 and 28 on another hollow shaft 29,whose uppermost part located inside the carrier beam 11 is rotatably,but axially immovably arranged on the lower, pin-shaped end of a carrierblock 30, which is in the form of a body of revolution and whose upperpart forms a flange which is secured to the top wall of the beam. Alsothe upper end of the hollow shaft 26 extends through an opening in thebeam bottom, and this end part mounts a crown wheel 31 which is locatedinside the beam and which is engaged with a bevel pinion (not shown) ondrive shaft sections (not shown) extending in the longitudinal directionof the beam to their respective adjacent rotors. One of the drive shaftsections is drivingly connected with the power take-off of the tractorthrough a transmission mechanism (not shown) so that the rake rotors canbe driven from this.

The lower end of the inner hollow shaft 29 mounts an arm 32 on whoseouter end a wheel fork 33, which carries an air rubber wheel 34, ispivotally secured. The wheel fork 33 is connected through a link 35 withthe lower end of a rod 36, which extends through and is slidable in thehollow shaft 29 and a central bore in the carrier block 30 as well as asleeve 37 rotatably mounted in a cylindrical recess in the upper side ofthe block. The upper end of the rod 36 positioned above the carrier beam11 is connected through a link 38 with one arm 39 of an angle lever,which is pivotally mounted on the bracket 15 at a pivot 40, and whoseother arm 41 is provided with a slot 42 which rotatably and slidablyreceives a pin 43 which is rotatably mounted on the end of the screwspindle 17.

When the inclination of the rake rotors is changed by rotating the screwspindle 17, e.g. in a direction such that the nut 16 is moved outwardlyon the spindle, the carrier beam 11 pivots about the shaft 13 so thatthe angle of the rotor axes with the vertical is reduced. Since thepivot 40 of the angle lever participates in the pivotal movement of thebeam, while the pin 43 connected with the angle lever 41 is stationary,the angle lever is simultaneously rotated clockwise, thereby lifting therod 36 and the wheel 34. This compensates for the increase in theminimum distance a of the rake means 25 from the ground, which is causedby the change in the angle of the rotor axes with the vertical.

The rotatable sleeve 37 mounts a disc 44 which is positioned on thecarrier block 30 and which is firmly connected with the upper end of thehollow shaft 29 through a bolt 45 which is parallel with the rotor axisand extends through a curved slot in the carrier block 30, the carrierarm 32 of the travelling wheel 34 being mounted on the hollow shaft 29.One end of a Z-shaped control arm 46, which extends through an openingin the beam wall, is welded on the upper side of the rotatable disc 44,and the other end of the control arm 46 is rotatably connected with acontrol rod 47 extending along the beam. Axial movement of this controlrod thus causes the disc 44 to rotate and thereby the hollow shaft 29carrying the wheel, which is thus steerable.

In FIG. 2 the parts corresponding to those in FIG. 1 are designated bythe same reference numerals as in FIG. 1.

In the embodiment shown in FIG. 2 the hub disc 22 is secured on a roundmember 48 which is slidable, but fixed against rotation on a hollowrotor shaft 49, which is in turn rotatably, but axially immovablymounted on a center shaft 50, whose upper end mounts the crown wheel 31positioned in the bottom of the carrier beam 11. The upper end of thecenter shaft 50 extending through the crown wheel mounts a disc 51,which is firmly connected with the rotatable disc 44 upwardly in thecarrier beam and thereby with the control mechanism 46, 47 through thebolt positioned in the vicinity of the periphery.

A drive shaft 52, which is driven by the tractor in a known manner (notshown), here extends uninterruptedly through the carrier beam 11 andcarries a bevel pinion (not shown) adjacent each crown wheel, said bevelpinion being engaged with the crown wheel in question to drive thehollow shaft 49 and the rake rotor 21 through the round member 48.

A control shaft 53, which extends in parallel with the drive shaft 52,is rotatably journalled in the carrier beam 11, said control shaftcarrying at each rotor shaft an arm 54, which emerges through an openingin the rear wall of the beam and is thus connected with a preferablyhexagonal rod 55, which is parallel with the rotor axis and is axiallyslidably controlled in control projections 56 on the beam, such thatthis rod is displaced in parallel with the rotor axis when the controlshaft 53 rotates. An inwardly extending angle arm 57 on the lower end ofthe rod 55 carries a rotatable roller 58 on its inner end, said rollerbeing positioned between a flange 59 on the round member 48 and theupper side of the rotor hub disc. Another roller 60 is located betweentwo radial shoulder surfaces on the round member 48 below the rotor hubdisc 22 and is rotatably mounted on an angle arm on the upper end ofanother preferably hexagonal rod 61, which is parallel with the rotoraxis and is axially slidably guided in a cross-sectionally U-shapedguide fitting 62 on an arm 63, which is secured to and extends forwardlyfrom the lower end of the center shaft 50. This arm 63 pivotally mountsa wheel fork 64, which carries the air rubber wheel 34 and has an anglearm 65 so connected with the rod 61 through a link 66 that the wheelfork pivots when the rod is displaced.

An additional arm 67 is secured on the guide shaft 53 opposite the screwspindle 17, said arm 67 defining together with the arms 54 an anglelever and extending down through an opening in the bottom of the carrierbeam. The outer end of this arm is rotatably connected with the lowerend of a double-curved articulated rod 68, which extends externally ofthe drive shaft 52 up through an opening in the top wall of the beam,and whose upper end is rotatably connected with the stationary end ofthe screw spindle 17.

If the screw spindle is rotated e.g. in such a direction that the nut 16moves outwardly on the spindle, the carrier beam 11 pivots about theshaft 13 so that the angle of the rotor axes with the vertical isreduced. Also the distance between the nut 16 and the upper end of thearticulated rod 68 is reduced, causing the lower end of said rod toexert a pull in the arm 67 and to rotate the control shaft 53counterclockwise. The arms 54 then press the rods 55 downwards, and thismovement is transferred through the rollers 58, the rotor hub discs 22,the round members 26 and the rollers 60 to the rods 61, which therebypivot the wheel fork 64 counterclockwise through the link 66. Thiscompensates for the increase in the minimum distance a of the rake means25 from the ground, which is caused by the change in the angle of therotor axes with the vertical.

In both of the two structures described above the wheel height isautomatically changed as the rotor axis angle changes, the reason beingthat the end of the screw spindle 17 is stationary. FIG. 3 shows anamended embodiment of a part of the adjustment mechanism, enabling thewheel height to be changed independently of the rotor inclination. Inthis amended embodiment the screw spindle 17 is hollow and surroundsanother screw spindle 70 having the same pitch, which is threadedlyengaged with a nut 71 mounted on the end of the screw spindle 17. Inthis structure it is the end of the inner, axially adjustable screwspindle 70 which is connected with the angle lever arm 41 in FIG. 1 andwith the link 68 in FIG. 2. This connection point is thus stationaryhere too, as long as the inner spindle does not rotate, but isadjustable.

The details of the structures shown and described can be modified inmany ways within the scope of the invention.

What is claimed is:
 1. A tedder having a main frame intended forsuspension from a tractor and a carrier beam which is pivotallyconnected to said main frame for pivotal movement about a horizontalaxis, a plurality of rake rotors, which are rotatable about theirrespective substantially vertical axes, being suspended from saidcarrier beam, each of said rake rotors being supported by a travellingwheel whose height position with respect to the carrier beam isadjustable by means of a height adjustment means slidable in parallelwith the rotor axis, said tedder having an angle adjustment mechanismpreferably activatable from the driver's seat of the tractor to pivotthe carrier beam, characterized by an angle lever which is rotatableabout an axis stationary with respect to the carrier beam, one arm ofsaid angle lever being connected with a member, said member being partof the angle adjustment mechanism and stationary with respect to themain frame, so that movement of the carrier beam with respect to themain frame causes rotation of the angle lever, the other arm of saidangle lever being connected with the height adjustment means fordisplacing said height adjustment means and travelling wheel uponrotation of the angle lever.
 2. A tedder according to claim 1,characterized in that the connection between said one arm of the anglelever and the member stationary with respect to the main frame isestablished by means of a link arranged between said one arm and thestationary member.
 3. A tedder according to claim 1, characterized inthat the connection between said one arm of the angle lever and themember stationary with respect to the main frame is established by aslot in said one arm receiving a pin which is firmly connected with thestationary member.
 4. A tedder according to claim 1, characterized inthat the carrier beam includes a support arm having one end secured tosaid carrier beam, the other end of said support arm being pivotallysecured to the main frame, and a second upwardly extending support armsecured to the carrier beam, said second support arm including arotatably mounting nut, said member forming part of the angle adjustmentmechanism including a threaded spindle engaged with said nut to adjustthe carrier beam when the threaded spindle is rotated.
 5. A tedderaccording to claim 1, wherein the carrier beam contains a through driveshaft for operating the rake rotors, characterized in that said one armof the angle lever is firmly mounted on a control shaft, which isrotatably journalled in the carrier beam and extends in parallelrelation with the drive shaft past all the rotors, said control shaftincluding an arm opposite each rotor, said arm on the control shaftbeing connected with a rod arranged on the exterior of the carrier beamand being slidable in parallel with the axis of the rotor, said rodbeing displaced by rotation of the control shaft, said rod carrying aroller in rolling contact with either of two flanges on a sleeve, whichcarries rotor arms and is slidable on, but fixed against rotation withrespect to a rotor shaft, said flanges being located above a rotor hubdisc, a second pair of flanges being provided below said disc on thesleeve, said second pair of flanges having interposed between them asecond roller whose shaft is connected with the height adjustment means.6. A tedder according to claim 1, wherein the drive shaft for the rakerotors contained in the carrier beam is divided into sections betweenthe rotor shafts, characterized in that the rotor shafts are hollow, andthat the height adjustment means are formed by a slidable rod, which isarranged in each rotor shaft and whose upper end protrudes from thecarrier beam, and are firmly connected with each other and articulatedto the second arm of the angle lever, which is common to all rotors.